Search for dissertations about: "jet noise"

Showing result 1 - 5 of 39 swedish dissertations containing the words jet noise.

2. 1. Study of Supersonic Jet Noise Reduction using LES

   Author : Haukur Hafsteinsson; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; G3D; Supersonic Jet; PIV; CD-nozzle; CFD; Compressible flow; CAA; Noise Reduction; LES; Flow Control;

   Abstract : Increases in air traffic and denser population around airports have led to stricterregulations on aircraft noise. High noise levels from high-speed aircraft can causehearing damage in pilots and the airfield personnel. The engine is the main sourceof noise of all jet aircraft and is therefore a key component for improvement. READ MORE

4. 2. Large Eddy Simulation for the Analysis of Supersonic Jet Noise Suppression Devices

   Author : Markus Olander Burak; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; fluidic injection; mixer-ejector; jet noise; Kirchhoff; forward flight effects; LES; acoustic liner; supersonic turbulent jets; broadband time-domain impedance boundary condition; chevrons; shock-associated noise; CAA; aeroacoustics;

   Abstract : Stricter noise regulations for commercial and military aircraft have increased interest in noise reduction techniques within the aerospace industry. To meet the requirements, new noise suppression technologies have to be developed and numerical methods need to be validated and possibly improved for the correct assessment of these technologies. READ MORE

5. 3. Noise from jet nozzles used in steel cutting

   Author : Siv Leth; Luleå tekniska universitet; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Strömningslära; Fluid Mechanics;

   Abstract : .... READ MORE

6. 4. Multi-Disciplinary Conceptual Design of Future Jet Engine Systems

   Author : Konstantinos G. Kyprianidis; Stephen O. T. Ogaji; Riti Singh; Herbert Saravanmuttoo; UK Cranfield University; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Gas Turbine; Intercooled; Recuperated; Turbofan; Future; Simulation; Performance; Aircraft; Emissions; Multi-disciplinary; Jet Engine; Energy- and Environmental Engineering; energi- och miljöteknik;

   Abstract : This thesis describes various aspects of the development of a multi-disciplinary aero engine conceptual design tool, TERA2020 (Techno-economic, Environmental and Risk Assessment for 2020), based on an explicit algorithm that considers: engine performance, engine aerodynamic and mechanical design, aircraft design and performance, emissions prediction and environmental impact, engine and airframe noise, and production, maintenance and direct operating costs.As part of this research effort, a newly-derived semi-empirical NOx correlation for modern rich-burn single-annular combustors is proposed. READ MORE

7. 5. A Study of Subsonic Turbulent Jets and Their Radiated Sound Using Large-Eddy Simulation

   Author : Niklas Andersson; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Two-Point Space-Time Correlations; CAA; Jet Noise; LES; Kirchhoff; Coaxial Jets; Heated Jets; Aeroacoustics;

   Abstract : Stricter noise regulation for near-ground operations has made noise reduction in commercial aircraft a topic of growing interest in the aerospace industry. To meet airworthiness requirements new noise reduction technologies have to be developed and numerical methods for correct assessment of these technologies are desirable. READ MORE